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24-Hour pH Probe Study

pH Probe Study

At UPMC Children's Hospital of Pittsburgh, we believe parents and guardians can contribute to the success of this test and we invite you to participate. Please read the following infor­mation to learn about the test and how you can help. 

Fast Facts About 24-Hour pH Probe Study

  • The 24-hour pH probe study is a test that uses a thin probe or tube placed in the esophagus or food pipe that connects the mouth to the stomach to help your doctor diagnose and treat acid reflux.
  • Your child must eat breakfast by 7 a.m. On the day of the test, he or she may have clear liquids until 10 a.m.
  • Placement of the probe takes only about 10 minutes, but readings are taken over a 24-hour period. For this reason, an overnight hospital stay is required. 

pH Probe StudyA pH probe study is a test to measure the amount and seriousness of acid juices that may be backing up into your child’s esophagus (ee-SOFF-a-gus), the tube in the neck that food passes through on its way to the stomach. The purpose of the test is to see if your child has acid reflux and help your doctor decide how to best treat it.

  • A very thin probe will be passed through the nose and into the esophagus. An X-ray will help make sure the probe is in the right place.
  • The probe is connected to a small monitor that will record acid levels over a 24-hour period. 
  • Information from the test gives ­doctors detailed information about your child’s acid reflux that cannot be learned from a physical examination or other kinds of tests. 
  • On the day of the test, your child should eat a normal breakfast before 7 a.m. Your child may have clear liquids until 10 a.m.
  • Follow your doctor’s specific orders about whether or not your child should take his or her medicines before the test.

Pack a small bag of clothing and items of special interest to your child, such as books, videotapes and toys, to keep him or her busy during the overnight stay. You may also bring along a "comfort" item — such as a favorite stuffed animal or "blankie" — for your child to hold during the placement of the probe.

We welcome your help and support during this test. One of the most important roles of a parent or guardian is to help your child stay calm and relaxed before and after the test. The easiest way to do this is for you to stay calm.

  • We encourage you to talk to your child and hold his or her hand before the probe is placed. 
  • Placement of the probe involves the use of X-rays. Women who are pregnant or believe they may be pregnant should limit exposure to X-rays. In this case, please bring another adult who can stay with your child during the placement of the probe.
  • Please do not distract the medical team or interrupt the test in any way.
  • We welcome your questions, but please ask them either before or after the test. 
  • The 24-hour pH probe test will be done while your child is an inpatient for an overnight stay at Children’s Hospital.
  • Your child will be called to an examination room and you will be asked some screening questions by one of the doctor’s assistants or nurses.
  • Any questions or concerns about your child’s test can be asked at this time. 
  • Your child will be asked to remove any jewelry he or she might have on and give it to you. He or she also will be asked to change into a hospital gown.
  • Your child will be taken to the Pediatric Radiology Department at UPMC Children's Hospital of Pittsburgh.
  • The placement of the pH probe will be done in the Radiology Department.
  • The pH probe is a thin tube about the size of a cooked spaghetti noodle that is soft and bends easily.
  • The end of the probe is placed through the nose and into in the esophagus. The probe will be taped to your child’s cheek to prevent it from moving and making your child uncomfortable during the test.
  • The probe is connected to a small computer that records pH or acid levels for 24 hours. Testing will begin once your child returns to his or her hospital room. 
pH Probe Study

Once the probe has been placed, your child will be taken to a hospital room where he or she will stay for 24 hours.

  • The parent or guardian staying with the child will be asked to help keep him or her from pulling out the probe. If it is removed, the probe will have to be put in again or the test will be cancelled.
  • A young child may need to have "No-No’s" put in place so he or she does not pull out the probe. These "No-No’s" are soft restraints that keep him or her from bending at the elbows.
  • The parent or guardian who stays with the child will be asked to make notes related to the test as it is being done. Instructions for filling out the notes form will be given on the day of the testing. Written instructions will also be available in the room.
  • While in the hospital, your child will need to eat lunch, dinner, a bedtime snack and breakfast the next morning.
  • Eating is only allowed at meals and snack time. Your child may not eat anything in-between these times.
  • We encourage you and your child to leave the room to take a walk or go to the playroom. 
  • The probe will stay in place for 24 hours to record information about the acid juices in the esophagus and stomach.
  • After breakfast the next day, a nurse will take out the probe. Taking out the probe is much easier than putting it in. 
pH Probe Study
  • Once the probe is out, you will be given instructions for going home.
  • Your child’s doctor will call you in ­several days to discuss the results of the test.
  • After the test, your child can eat his or her normal diet.
  • Your child may have a sore throat and be tired for a day or so following the test. 
  • If your child develops a fever, or is vomiting, call 412-692-5180 for immediate attention. If you have other questions or ­concerns, call the GI office at 412-692-5180.

If your child has any special needs or health issues you feel the doctor performing the test needs to know about please call the GI procedure nurse at UPMC Children's Hospital of Pittsburgh before the test at 412-692-5944. It is important to notify us in advance about any special needs.